GCRL Involves Students and Local Anglers in Research on Southern Flounder in Mississippi Waters

Although southern flounder is a popular sport fish on the Mississippi Gulf Coast, there are still many open questions about this mysterious flatfish species. For example, it is known that mature southern flounder migrate to offshore waters for spawning in the winter, but it is uncertain where, when, or how often spawning occurs. Researchers at The University of Southern Mississippi Gulf Coast Research Laboratory (GCRL) hope to answer critical questions such as these about southern flounder. 

See flyer for more information on how to compete for a 45-quart YETI cooler prize!

Why Southern Flounder?
Southern flounder (Paralichthys lethostigma) is the most commonly harvested flatfish species that occurs in coastal Mississippi waters. The southern flounder population is therefore a valuable resource in the northern Gulf of Mexico, and is primarily harvested by recreational anglers using hook-and-line fishing or gigging. Despite the value of this species, information about the life history of southern flounder in this area is limited.

All southern flounder collected are measured for length and weight. The sex of each fish is determined and reproductive organs are preserved. Otoliths are also removed for aging.

The fascinating biology of southern flounder involves a complex metamorphosis from upright swimming larvae to a flatfish body form with both eyes on the left side of the head. These fish are known to migrate to offshore waters for spawning in the winter months. Larval southern flounder are then transported back to the estuaries by tides and currents, where they grow and develop in near-shore waters. Females grow much faster than males and reach overall larger body sizes, which means that the majority of harvested southern flounder are females. For more information on flounders in Mississippi, check out the GCRL flounder profile: https://gcrl.usm.edu/public/fish/flounder.php



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Otoliths are inner-ear structures that grown in rings (similar to growth rings in a tree) and can be used to age fish. Pictured is an otolith from a 2-year old southern flounder.
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Sampling from local fishing tournaments has been an important part of this research effort.












Wanted - Flounder Poster pdf

Project Details
This research project has two main goals:

Read prepares to release a tagged cobia.
Captain Sonny Schindler of Shore Thing Charters and Morgan Corey, GCRL Graduate Student, with a nice catch of flounder.
  1. To describe the age and growth patterns, and
  2. To characterize the reproductive biology of southern flounder in Mississippi waters.

The age of these fish is estimated by counting yearly growth rings on otoliths (inner-ear stones), which grow like the rings in a tree. Studying reproductive biology involves looking at the tissue on a cellular level to describe the development of reproductive organs leading up to, during, and after spawning events. This research effort will provide an understanding of the age and size at which female southern flounder spawn and their ability to contribute new fish to the population. This information will help conserve a valuable marine resource in coastal Mississippi.

The biggest challenge of this research is sampling enough fish to describe the Mississippi-wide southern flounder population. Over the past year, the research team has successfully collected samples from over 400 fish ranging in size from 4” to 24”. Gigging has been the most common technique used, and many samples have been collected from local fishing tournaments. Sampling for this project will continue through February 2016 in the hopes of collecting southern flounder throughout their winter spawning season.

What makes this project unique?

Read prepares to release a tagged cobia.
Unusual coloration on the bottom side of a southern flounder.

The project is titled INvolving Student Populations In Research and Education (INSPIRE) and is unique in that it actively engages high school and community college students from the three coastal counties of Mississippi. High school and community college students have limited opportunities to be involved in and understand the research process. This limitation can cause students to be discouraged in pursuing further education and careers in the sciences. Project INSPIRE challenges and engages students to fully participate in the research project that will further the understanding of the southern flounder within the Mississippi Sound. As a result of this project students will gain a vested interest in our coastal resources and will directly contribute to the knowledge base that resource managers can utilize to make informed decisions on this fishery. It is also anticipated that some of the students participating in this project will go on to pursue science-based education and careers.

Project INSPIRE also engages local anglers, charter captains, state agencies, and conservation groups such as CCA. This project has allowed GCRL to strengthen its partnerships with the local fishing community and provides them the opportunity to contribute to GCRL’s research efforts.

How to get involved
Local anglers are a key component to the success of this project, and this research project has received great support from the community. Because southern flounder are scarce in near-shore waters during the winter, the assistance of anglers in collecting fish during December through February is invaluable.

The GCRL research team is offering a prize of a new 45 quart YETI Tundra cooler for submitting the heaviest cumulative weight of southern flounder over 16” caught from December 2015 through February 2016.

See flyer for more information on how to compete for a 45-quart YETI cooler prize!

Leader Board

All sizes and developmental stages of southern flounder are of interest for this research.

Anglers can get involved by contacting researchers at GCRL when a southern flounder is caught. The research team will weigh and measure each fish, and remove only the otoliths and reproductive organs. The sample collection process does not damage the fillets in any way, and anglers can keep the fillets after the fish has been weighed. The fish must be kept whole on ice and submitted within 24 hours of being caught. Any legal-sized southern flounder is valuable to the research, particularly those caught offshore. Anglers may bring the fish to GCRL or arrangements can be made to meet a team member at a convenient location.

Anglers interested in participating should contact Morgan Corey at 228.818.8816 (office), 419.348.7431 (cell), Morgan.Corey@eagles.usm.edu or Sam Clardy at 228.818.8885 (office), Samuel.clardy@usm.edu. Funding for this research is provided by the Mississippi Tidelands Trust Fund Program, and administered by the Mississippi Department of Marine Resources.  

Funding for this research is provided by the Mississippi Tidelands Trust Fund and administered by the Mississippi Department of Marine Resources.